Modeling the Potential Effects of New Tobacco Products and Policies: A Dynamic Population Model for Multiple Product Use and Harm

Background
Recent declines in US cigarette smoking prevalence have coincided with increases in use of other tobacco products. Multiple product tobacco models can help assess the population health impacts associated with use of a wide range of tobacco products.
Methods and Findings
We present a multi-state, dynamical systems population structure model that can be used to assess the effects of tobacco product use behaviors on population health. The model incorporates transition behaviors, such as initiation, cessation, switching, and dual use, related to the use of multiple products. The model tracks product use prevalence and mortality attributable to tobacco use for the overall population and by sex and age group. The model can also be used to estimate differences in these outcomes between scenarios by varying input parameter values. We demonstrate model capabilities by projecting future cigarette smoking prevalence and smoking-attributable mortality and then simulating the effects of introduction of a hypothetical new lower-risk tobacco product under a variety of assumptions about product use. Sensitivity analyses were conducted to examine the range of population impacts that could occur due to differences in input values for product use and risk. We demonstrate that potential benefits from cigarette smokers switching to the lower-risk product can be offset over time through increased initiation of this product. Model results show that population health benefits are particularly sensitive to product risks and initiation, switching, and dual use behaviors.
Conclusion
Our model incorporates the variety of tobacco use behaviors and risks that occur with multiple products. As such, it can evaluate the population health impacts associated with the introduction of new tobacco products or policies that may result in product switching or dual use. Further model development will include refinement of data inputs for non-cigarette tobacco products and inclusion of health outcomes such as morbidity and disability.

研究背景
近年来美国香烟吸烟率持续下降，而同期其他烟草产品的使用量却不断攀升。多产品烟草模型可用于评估使用各类烟草产品对人群健康造成的影响。

研究方法与研究结果
本研究构建了一款多状态动力学系统人群结构模型，可用于评估烟草产品使用行为对人群健康的影响。该模型纳入了与多产品使用相关的各类行为转变过程，包括初始使用、戒断、产品切换以及双重使用。模型可追踪全体人群及分性别、分年龄组的烟草产品使用流行率与烟草使用归因死亡率。通过调整输入参数值，该模型还可估算不同模拟场景下上述结局的差异。为验证模型的应用效能，本研究首先预测了未来香烟吸烟率与吸烟归因死亡率，随后在多种产品使用假设场景下，模拟了一款假设性新型低风险烟草产品的引入所产生的健康影响。此外，本研究开展了敏感性分析，以探究因产品使用与风险相关输入参数的差异，可能带来的人群健康影响范围。研究结果表明，香烟吸烟者转用低风险产品所带来的潜在健康收益，可能会随着该产品初始使用者的增加而被逐步抵消。模型结果显示，人群健康收益对产品风险、初始使用、产品切换及双重使用行为尤为敏感。

研究结论
本模型纳入了多产品使用场景下各类烟草使用行为与相关风险，因此可用于评估引入新型烟草产品或推行可能引发产品切换或双重使用的政策时，对人群健康产生的影响。未来模型开发将包括完善非香烟类烟草产品的输入数据，并纳入发病率、残疾率等其他健康结局指标。